XML 55 R37.htm IDEA: XBRL DOCUMENT v3.8.0.1
Components of Net Periodic Pension Cost (Detail) - Pension Plans, Defined Benefit - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Defined Benefit Plan Disclosure [Line Items]        
Service cost, net of employee contributions $ 6.8 $ 7.5 $ 20.1 $ 22.0
Interest cost 4.8 4.8 14.4 14.2
Expected return on plan assets (8.3) (8.0) (24.8) (24.2)
Amortization 3.3 2.6 9.8 7.8
Curtailment (1.7) 0.0 (1.7) 0.0
Net periodic pension cost $ 4.9 $ 6.9 $ 17.8 $ 19.8